Final answer:
The gray matter on the surface of the cerebral hemispheres is known as the cerebral cortex, which is a part of the cerebrum responsible for higher brain functions and is characterized by its wrinkled appearance with gyri and sulci.
Step-by-step explanation:
The gray matter on the surface of the cerebral hemispheres is called the cerebral cortex. The cerebrum is the larger part of the brain that includes the cerebral cortex, and it is responsible for higher neurological functions such as memory, emotion, and consciousness. The cerebral cortex is characterized by wrinkles and folds known as gyri (singular: gyrus) and sulci (singular: sulcus), giving it a distinctive wrinkled appearance. It is this outer layer that is involved in many important brain functions including sensory perception, controlling motor functions, and involved in complex thought processes. Each half of the cerebrum is called a cerebral hemisphere, and the two are connected by a thick bundle of axons known as the corpus callosum, which facilitates communication between them.